1. Field
Embodiments of the present invention relate to a fuel cell system and a driving method thereof.
2. Description of Related Art
A fuel cell is a device that electrochemically generates electric power using a fuel (e.g., hydrogen or a reformed gas) and an oxidizing agent (e.g., oxygen or air), and directly converts the externally supplied fuel (e.g., fuel that is continuously supplied from the outside) and the oxidizing agent to electrical energy by an electrochemical reaction.
As an oxidizing agent of the fuel cell, pure oxygen or air containing a large amount of oxygen is used. As fuel for the fuel cell, fuel containing a large amount of hydrogen that is generated by reforming pure hydrogen or hydrocarbon-based fuel (e.g., LNG, LPG, or CH3OH) is used.
Hereinafter, for better comprehension and ease of description, among fuel cells, a polymer electrolyte membrane fuel cell (PEMFC) is described. The PEMFC has high output density and energy conversion efficiency, and can be operated at a low temperature of 80° C. or lower and can be sealed in a small size, and is thus used as a power source in various fields, such as nonpolluting vehicles, home electricity generation systems, mobile communication equipment, military equipment, and medical equipment.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and, therefore, may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.